Radio Frequency Identification (RFID) is utilized in a variety of applications with RFID readers communicating with RFID tags for purposes of identification, location, tracking, and the like. In an exemplary RFID application, an RFID reader may be mounted overhead (e.g., ceiling mounted) relative to a plurality of RFID tags. For example, in a retail, warehouse, etc. scenario, the RFID reader may be mounted above the RFID tags and their associated objects. Conventional antenna designs may be utilized in overhead configurations but with disadvantages. For example, a Yagi antenna may be utilized in the RFID reader but requires a certain amount of length hanging down from the overhead location. Additionally, a phased antenna array could also be used in the RFID reader, but such a solution requires electronic beam steering, adding complexity and cost. Alternatively, a chandelier antenna system (i.e., a series of antennas arranged in a circle collectively resembling a chandelier) could also be used in the RFID reader, but this may also require additional cost and size.
Accordingly, there is a need for an RFID antenna apparatus and method overcoming the aforementioned limitations and providing high gain, directionality, and orientation insensitivity while occupying minimal volume in overhead configurations.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.